Scalable coded image transmissions over peer-to-peer networks

In this paper, we study the transmission of scalable coded images over peer-to-peer networks. Scalable coded images share common prefix of their resulted bit streams even when coded using different bit rates. This property implies two important consequences on the peer-to-peer system when compared to transmission of nonscalable coded images: (1) there exists a many-to-one relationship between supplying and requesting peers as multiple peers with the code images in different bit rates become eligible as supplying peers; and (2) the set of supplying peers is dynamic over time as the peers in the supplying set may finish transmission at different times. When we transmit the requested image from multiple supplying peers to a requesting peer, it is very important to design optimal peer assignment algorithms to minimize the overall transmission time for the requesting peer. For this purpose, we first establish a sufficient property for the optimal peer assignment vector, and then design an optimal media segmentation algorithm based on the sufficient property. Finally, we compare the performance of the proposed optimal media segmentation algorithm with two heuristics and verify its superior performance.